Image analysis in general has become a valuable tool in a wide variety of medical applications such as for the diagnosis of many diseases. Depending on the medical application, use is made of certain agents detectable for the image analysis, such as contrast agents, which need to be injected to the patient in order to visualize a certain tissue or organ. While the use of these agents is crucial for certain imaging techniques, these agents might also be harmful to the patient, depending on the amount injected to the patient.
In the field of X-Ray angiography procedures, the interventional radiologist/cardiologist performing the procedure is responsible for deciding which contrast medium will provide the best images, depending on which part of the body is being imaged and the type of the procedure. This decision will be based on the patient information, such as medical history and recent examinations (hours to a few days) involving contrast media.
Commonly used contrast media such as Iodine or Gadolinium contrast media are generally very safe for patients with normal kidney function, however there is possible increased risk for patients with limited kidney function (e.g. older people, on dialysis patients, or patients which had a kidney surgery or kidney disease in the past). These risks might include:                Severe allergic reaction,        Contrast Induced Nephropathy: It can result in temporary, prolonged or permanent worsening of kidney function which could result in the need for temporary or permanent dialysis in the most severely affected patients.        
To reduce these risks, there is a maximum recommended amount of contrast agent that the patient should receive during the procedure. Other than the patient medical history, this maximum depends on the size, weight and age of the patient.
Although the amount of contrast agent injected can be captured and displayed in a computerized injector system, today the manual syringe injections remain untracked during the procedure, as they are usually tracked manually by an operator when a bottle of medium comprising the contrast agent is finished or at the end of the exam. This manual tracking however is both error-prone and imprecise. Furthermore, as the manual tracking normally is merely based on counting the used bottles of medium, no real time-tracking of the volume of medium injected to the patient is possible.
Accordingly, continuous monitoring of the contrast volume delivered during the procedure is important in order to take the appropriate decision that balances clinical outcomes and quality of care, mainly on contrast-sensitive patients. Thus, there is the need for an automatic and reliable monitoring functionality applicable to manual injection events during the procedure.